Conventional combination treadmill and stair-climbing machines typically include a frame, a treadle assembly pivotally coupled to a base of the frame, and a resistance element coupled to the treadle assembly and an upright portion of the frame. The treadle assembly is configured to travel a distance in a generally upward direction and a generally downward direction relative to the base of the frame. A piston rod of the resistance element extends when the treadle assembly is in the upward direction. When the treadle assembly travels in the downward direction, the piston rod is retracted or pushed into the resistance element.